The present invention relates to a powered toothbrush construction and method for cleaning teeth and related embrasures. It relates specifically to apparatus and methods for cleaning plaque from tooth surfaces and for cleaning embrasures such as the spaces between adjacent teeth at the gum line, the crevices in the molar occlusal surfaces of the teeth, and the gingival (gum) cuff area between the tooth and the gum. It is particularly directed toward hard to reach and clean embrasures and surfaces such as the spaces between orthodontic appliances and the teeth, the spaces between the roots of a tooth and above the gum line as existing after periodontal (gum) surgery, and the spaces between crowns and bridgework and related teeth and gums.
The problems of effectively removing plaque from tooth surfaces (other than from relatively flat, easy to reach tooth surfaces) are well recognized in the dental field. Thus, for example, it is recognized that it is difficult to effectively remove plaque from the tooth surfaces adjacent the gum line and the gingival cuff around each tooth and from those surfaces of the teeth which face adjacent teeth. The conventional manually actuated toothbrush does not properly clean these surfaces.
To get at the surfaces and spaces between adjacent teeth, dentists usually recommend the use of dental floss, but even dental floss has limitations which can mitigate against completely effective use in these areas. For example, dental floss, if used properly, is effective to remove food particles from embrasures existing between adjacent teeth, and it is also effective to remove plaque from convex surfaces where the dental floss can be engaged with a curved surface having this configuration. However, the dental floss will not reach into any concave surfaces or crevices, and therefore cannot remove plaque from such surfaces. It is also difficult to remove plaque from inner (tongue side surfaces) and outer (cheek and lip side) tooth surfaces near the gum line with dental floss. Dental floss also suffers a disadvantage in that the user often does not make the most effective use of it. As a practical matter, dental floss also cannot be used to clean the spaces between orthodontic appliances and teeth or to clean embrasure areas such as those existing between the roots of a tooth and a gum line which has been lowered by periodontal surgery or those embrasure areas existing between a crown or bridgework and an associated tooth or gum surface.
A number of power driven toothbrushes have been designed and constructed in attempts to remedy the limitations of the conventional manually operated toothbrush, but these power driven toothbrushes have not effectively overcome the problem of removing plaque and food particles from many of the problem areas noted above. The power driven toothbrushes developed in the prior art have in most cases been directed toward the concept of reciprocating the toothbrush in a direction generally either along the length or across the width of the brush head in a wiping type of action.
See, for example, U.S. Pat. No. 3,702,487 to Sung, issued Nov. 14, 1972 which shows a mechanized arrangement for aligning the bristles with the tooth striations and moving the bristles in a sweeping brush stroke for brushing from the base of the tooth toward the tip of the tooth. This type of brushing action corresponds with what has been considered to be the preferred dental practice, i.e. brushing along the length of the tooth and away from the gum.
Other motorized tooth brush constructions have been proposed for imparting a vibratory action to the brush head to assist in producing a massaging action of the brush head on the gums. U.S. Pat. No. 1,342,280 to Fitzgerald, issued June 1, 1920 and U.S. Pat. No. 1,703,642 to Sticht, issued Feb. 26, 1929 are examples of such vibratory toothbrush constructions. Each of these patents does produce some endwise movement of the bristles, but the amount of the movement is very restricted, and the brush head is intended to span several teeth so that any benefit that could be obtained by the slight amount of endwise vibratory movement of the bristles is largely dissipated by the damping and bridging effect that the elongated brush head produces as it bridges across several teeth. Each of the Fitzgerald and Sticht patents is primarily directed toward obtaining a slight massaging effect on the gums as the brush head is moved back and forth in its normal brushing sidewise movement.
In contrast, the brush head of the present invention is moved slowly and deliberately across each surface, embrasure, and gingival cuff in order to let the axial movement of the brush elements do the cleaning.
French Pat. No. 870,822, published Mar. 25, 1942 shows a power driven unit that can be used either as a massaging tool for fingernails or as a brush for teeth. In the brush configuration, a rotary brush is mounted for oscillation in a direction parallel to the axis of the brush so that the brush head is driven up and down along the outer (or along the inner) surface of a tooth by the vibrator as the brush is moved manually back and forth along the row of teeth. This is a further example of a power driven brush construction which reflects the more or less accepted dental thinking that the best brushing action is in a direction down the length of the tooth and parallel to the surface of the tooth.
The prior art toothbrushes have therefore not effectively solved the problems of effectively cleaning certain embrasures and related tooth surfaces normally occurring in mouths, e.g. deep crevices in molars, tooth surfaces near the gum line, the gingival cuff area, and the tooth surfaces of embrasures such as exist in the spaces between adjacent teeth above the gum line. Furthermore, the prior art toothbrushes have entirely failed to meet the needs for cleaning such specialized, hard to clean areas as the embrasures existing between crowns and bridgework and the gum, the spaces between orthodontic appliances and teeth, and the spaces between the tooth surfaces of tooth roots extending above the gum line after periodontal surgery. As a good example of the fact that, prior to the present invention, a definite problem existed in the cleaning of such embrasures created by periodontal surgery, it may be noted that some dental techniques suggested inserting pipe cleaners into these spaces to clean out food particles and to help remove some of the plaque build-up.
It is a primary object of the present invention to overcome the problems of cleaning tooth surfaces and embrasures as noted above.
It is a related and an important object to construct a power driven toothbrush and to provide a method of operation which not only prevents plaque build-up, tooth decay and the development of diseased gum conditions, but which also is effective to aid in curing certain diseased gum conditions. In this last regard, clinical evidence has documented that the brush of the present invention has reduced hypertrophied gingival (overgrown gum tissue) in a matter of days.
It is another object of the present invention to construct a powered toothbrush that debilitated persons can use, often without assistance, to do most of the work that is accomplished by dental floss.
It is a further, important object of the present invention to construct a powered toothbrush and to provide a method of tooth cleaning which effects deep cleansing and plaque removal in embrasures and in the gingival cuff with a cleaning action not possible with dental floss or prior art brushes.